My system is already built but i thought i would ask about a drain hose at the moment i drain from video card and i would much rather have a drain hose for it but what i need is suggestions on where to ad it
any info is appreciated thanks

The drain tube needs to be at the lowest point in your system. Sadly this is at the graphics card. Otherwise you will have to pick up your case and rotate it when draining, not fun with a corsair 800d.

You could try and rout the video card to reservoir hose through the grommets and out the backside and make the T junction at the lowest spot of the system in the backside of the case out of sight. Daz does this with his 800d build. He did use 3/8 tube though and yours looks like 1/2.